Walsh is thought to have cheated with his partner on the show, Katya Jones.

In a tweet beginning “My name is Rebecca Humphries and I am not a victim,” the actress gave her account of the relationship’s breakdown. According to Humphries, Walsh was aggressive with her and repeatedly called her a “psycho/nuts/mental” when she doubted him.

They deny having said something even when you have proof

If your partner regularly dismisses your memory of events, this could be a sign of gaslighting,” Mackintosh-Stewart explains. “They’ve made you a promise and you even have written evidence. And yet they outwardly deny it, causing you to think: ‘Maybe I just misinterpreted’.

“The more the gaslighter does this, the more you question your own reality and start accepting theirs.”

They project their own traits on to you

Whether it’s jealousy, greediness or a tendency to cheat, a gaslighting partner will often accuse you of these traits rather than admitting they are guilty of them.

“The purpose of this is to make you try and defend yourself and, in the process, distract you from the gaslighter’s own behaviour,” says Mackintosh-Stewart.

They tell outright lies

Gaslighting often manifests itself as your partner telling you outrageous lies, but never admitting to it.

“They blatantly lie even when you both know they’re lying,” Mackintosh-Stewart explains. “They do it with a straight face and it keeps you on edge.”

They give you positive reinforcement to set you off balance

Ever felt you’ve been built up, only to be knocked back down again? Mackintosh-Stewart says this is a key sign of a gaslighting partner.

“After cutting you down and making you feel worthless, they then attempt to build you up again and praise you. This is a calculated attempt to keep you feeling uneasy and to destabilise your self-worth.”

They wear you down over time

This one is particularly sinister. A gaslighter will grind you down gradually, explains Mackintosh-Stewart.

“A lie here, a snide comment there and then they ramp it up.” She adds: “Even the most self-confident people can get sucked in over time.”

If you or someone you know is experiencing abuse in a relationship, call the Freephone 24/7 National Domestic Violence Helpline, run by Women’s Aid in partnership with Refuge, on 0808 2000 247 or visit www.womensaid.org.uk.